Availability cascade – a self-reinforcing process in which a collective belief gains more and more plausibility through its increasing repetition in public discourse (or “repeat something long enough and it will become true”).

Availability heuristic – estimating what is more likely by what is more available in memory, which is biased toward vivid, unusual, or emotionally charged examples.

Bandwagon effect – the tendency to do (or believe) things because many other people do (or believe) the same. Related to groupthink and herd behaviour.

Bias blind spot – the tendency to see oneself as less biased than other people.

Choice-supportive bias – the tendency to remember one’s choices as better than they actually were.

Clustering illusion – the tendency to see patterns where actually none exist.

Confirmation bias – the tendency to search for or interpret information in a way that confirms one’s preconceptions.

Congruence bias – the tendency to test hypotheses exclusively through direct testing, in contrast to tests of possible alternative hypotheses.

Endowment effect – the fact that people often demand much more to give up an object than they would be willing to pay to acquire it.

Experimenter’s bias – the tendency for experimenters to believe, certify, and publish data that agree with their expectations for the outcome of an experiment, and to disbelieve, discard, or downgrade the corresponding weightings for data that appear to conflict with those expectations.

Focusing effect – the tendency to place too much importance on one aspect of an event; causes error in accurately predicting the utility of a future outcome.

Framing effect – drawing different conclusions from the same information, depending on how that information is presented.

Fundamental attribution error – the tendency for people to over-emphasize personality-based explanations for behaviours observed in others while under-emphasizing the role and power of situational influences on the same behaviour.

Halo effect – the tendency for a person’s positive or negative traits to “spill over” from one area of their personality to another in others’ perceptions of them.

Hindsight bias – sometimes called the “I-knew-it-all-along” effect, the tendency to see past events as being predictable at the time those events happened.

Illusion of control – the tendency to overestimate one’s degree of influence over other external events.

Illusory correlation – inaccurately perceiving a relationship between two events, either because of prejudice or selective processing of information.

Pareidolia – a vague and random stimulus (often an image or sound) is perceived as significant, e.g., seeing images of animals or faces in clouds, the man in the moon, and hearing hidden messages on records played in reverse.

Pessimism bias – the tendency for some people, especially those suffering from depression, to overestimate the likelihood of negative things happening to them.

Positive outcome bias – the tendency of one to overestimate the probability of a favourable outcome coming to pass in a given situation.

Primacy effect – the tendency to weigh initial events more than subsequent events.

Recency effect – the tendency to weigh recent events more than earlier events.

Selective perception – the tendency for expectations to affect perception.

Self-serving bias – the tendency to claim more responsibility for successes than failures. It may also manifest itself as a tendency for people to evaluate ambiguous information in a way beneficial to their interests (see also group-serving bias).

Semmelweis reflex – the tendency to reject new evidence that contradicts an established paradigm.

Status quo bias – the tendency to like things to stay relatively the same

Subjective validation – perception that something is true if a subject’s belief demands it to be true. Also assigns perceived connections between coincidences.

System justification – the tendency to defend and bolster the status quo. Existing social, economic, and political arrangements tend to be preferred, and alternatives disparaged sometimes even at the expense of individual and collective self-interest.

Ultimate attribution error – similar to the fundamental attribution error, in this error a person is likely to make an internal attribution to an entire group instead of the individuals within the group.